How to Save Money Using a Variable Speed Motor

WRITTEN BY:  Inyo Pools

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Many people are switching to variable speed motors or pumps to save around 75% in their electric bill. If you are paying $800 a year now with a single speed motor, you can drop that cost to $200 a year with a variable speed motor (Based on $0.15/KWH - 20,000 gallon pool). NOTE: PRICES SHOWN MAY HAVE BEEN REDUCED SINCE THIS GUIDE WAS WRITTEN. SEE PRODUCT PAGE FOR CURRENT PRICES.

Step by Step


Step 1

Parts of a Variable Speed Motor - A typical variable speed (VS) motor has three major parts: the motor itself, the drive that is bolted on top of the motor and the controller that sits on top of the drive. The drive provides electrical lines to the motor and contains the circuit boards used to control the motor. The controller has has a panel of buttons and a display that allow the user to program time and speed commands to the drive. In many cases the controller can be taken off the drive and mounted on a wall for easier accessibility to the panel.

Step 2

Overview of Common Features - Variable speed motors on the market today have many features in common. They offer up to 85% savings in operational costs with an average savings of 75% depending on your pool features. Most are wired for 230V and can run between 600 and 3450 RPM. Their max Total Horse Power (THP) is in the range of 2.3 to 3.45 HP. All have integrated programmable timers mounted on the top of the motor. Most can be programmed for up to 8 different speeds in 8 different time slots. All variable speed motors use permanent magnets technology in place of coiled wire used in standard induction single speed motors. All variable speed motors have a Totally Enclosed Fan Cooled (TEFC) design. These motors also run much quieter at full speed. At the lower speed you can hardly hear them at all.

Step 3

TEFC- Totally Enclosed Fan Cooled (TEFC) motors keep water and bugs out which prolongs their life to 3 times the life of a standard induction motor. The motor can be totally enclosed because the permanent magnet technology allows these motors to run much cooler and quieter than the standard induction motors.

Step 4

Operation - Each of the various functions of your pool requires a minimum water flow to operate. You would set your pump to run at the lowest RPMs required to generate the minimum required water flow. The filtrations system can operate at low water flow with typical motor speeds around 1000 RPM or less depending on the size of your pool and how long you want to run the pump. Suction cleaners typically run at around 2200-2400 RPM. Heaters require 20 to 40 Gallons Per Minute (GPM) so might run at around half speed or a little higher. You would probably want to run your Spa at up to full speed, 3450, for maximum effect. The speed required for any water features like waterfalls, bubblers, and laminars would depend on the desired height or projection.

Step 5

Setting Operational RPMs - Determining the minimum speed required to operate each feature is easy. For example, a heater will shut off if it doesn't have sufficient water flow (GFM) to prevent overheating. To determine where your heater shuts off for your particular pool system, set the pump's speed at a low rate of RPM and then increment it in steps until the heater kicks on. Add 50 RPM to account for system variations and you have your minimum RPM for heater operation. If you have a solar heating system, do the same process and check the RPM at which the cavitation in the pump stops. If the water flow is not sufficient to supply your pipes on the roof, the water flowing down the pipes by gravity may get ahead of the water coming up and you will start to get air in your lines. For a suction cleaner, look for optimum performance in the cleaner.

Step 6

Typical program - The current variable pumps have a digital control interface mounted on top of the motor from which you can program your different speeds and run times. A program for a typical pool might look like this: Suction cleaner - run at 2400 for 2 hours; Filtration - run at 1200 RPM for 16 hours; Spa run at 3450 for 2 hours or on demand. Most pumps have manual overrides to change settings temporarily.

Step 7

Savings - So where's the saving? A basic law in physics says that if you reduce the RPM of a motor by 1/2, you reduce the energy required to move that water to 1/8 the full speed energy. So, if it costs $2.20 a day to run my single speed motor for 8 hours, it would only cost 1/8 of that or $0.28 to run a variable speed motor for 8 hours. But, you say, where's the savings if I have to run the pump twice as long because I'm only moving half the water at half speed? Running a variable speed motor at half speed for 16 hours would cost twice the cost for 8 hours or $0.55 / day. That's still a huge savings of 75%.

Step 8

Cost for Typical Pool Program - Costing out the typical pool program provided above looks like this: If I run the filtration system at 1200 RPM instead of 1725 RPM (half speed), my energy cost drops even further to around 5%. Using the numbers above, 5% of $2.20 is $0.11 for 8 hours or a total of $0.22 for 16 hours. To run a suction cleaner at 2400 drops energy cost to about 40% of full RPM costs. 40% of $2.20 is $0.88 for 8 hours or a total of $0.22 for 2 hours. Running the Spa at full RPM (3450) for 2 hours would cost 1/4 of $2.20 or $0.55. Comparing the total costs: Single speed motor - 8 hours of filtration and cleaning and 2 hours of Spa costs $2.20 + $0.55 or a total of $2.75. Variable speed motor - 16 hours of filtration, 2 hours of suction cleaning and 2 hours of Spa costs $0.22 + $0.22 + $0.55 or a total of $0.99. That's a savings of 65% even with running the Spa at full speed for 2 hours. Without the Spa, you would save 80% ($0.44/$2.20). Note that these cost numbers are only representative and will vary based on your pool size and electricity costs, but the savings percentages are the same regardless of actual costs.

Step 9

Payback - How do you justify the cost of a variable speed pump or motor? A variable speed pump costs about $1200 or two to three times the initial cost of a comparable single speed pump. If you are just replacing the motor, a variable speed motor costs about $800. The cost savings is in operational costs. If you currently spend $800 a year, at 75% reduced operation costs, you will be spending $200 a year or $600 less a year. You could pay off the difference in cost in a little more than a year for the pump and somewhat under a year for just the motor. Plus these motors are sealed and built to last 3 times longer than the current single speed motors. You would have to buy 3 single speed replacement motors for every variable speed motor.

Step 10

GPM requirements - We touched on this above but a common concern with variable speed pumps is insufficient water flow to operate some features like a heater and a suction cleaner. The argument goes - If I have to reduce the motor's RPM and water flow to get meaningful savings, I can't operate some pool function. If I have to operate at higher RPMs, I lose all my saving. You saw the savings above with a suction cleaner. Let's add in the heater.

Step 11

Costs of running filtration with a suction cleaner and a heater. – If I run the heater at 2400 RPM for 8 hours a day to heat the pool at something above the required 40 GPM, I could run the cleaner for 2 hours in that same time slot. Then I would have to run the pump for another 4 hours for filtration at 1200 RPM to compensate for the lower flow rate. From the calculations in Step 7, my cost for 4 hours of filtration is $0.06 (8 hours was $0.11). Running the pump at 2400 for the heater/cleaner uses about 40% of the energy to run at full speed. From the numbers above, if it costs $2.20 to run a single speed (SS) pump for 8 hours, if will cost $40% of $2.20 or $0.88 to run the VS pump at 2400 RPM for 8 hours. The total cost of running the VS pump is $0.94 ($0.06+$0.88) for 12 hours. That’s a % savings of 57%.during the months that you have to run a heater. Note that this is just the cost of running the pump to circulate the water through the heater. This cost does not include the cost of fueling the heater.

Step 12

State Regulations - States are starting to regulate energy usage on pools. At some point we may all have to change over to variable pumps. California's Title 20 regulation requires that pumps > 1 THP must be 2-speed or variable speed and must have a control to default to low speed after being in high speed of an extended time. Florida just passed a similar regulation in March 2012, HB 849.

Step 13

Automatic adaptability - A single variable speed (VS) motor can be used to replace any size single or dual speed motor from 3/4 HP to 2.5 HP. By design a VS motor automatically adjusts to required torque. If you replace a 1 1/2 HP single speed motor with a 2.5 max HP VS motor, the VS motor will sense that the pumps wet end has an impeller for a 1 1/2 HP, and the motor will only use the energy required to drive that 1 1/2 HP impeller. Even at full speed, 3450 RPM, the VS motor will not exceed the energy required for a single 1 1/2 HP pump. In terms of costs, the cost of running a replacement 2.5 HP VS motor at 3450 RPM is no higher than the cost of the replaced 1 1/2 HP motor. In fact due to the permanent magnet design of the VS motor, the cost will be 85% cheaper at full speed.

Step 14

Comparison of pumps - As I mentioned above, most of the variable speed pumps on the market or just coming out now, have similar features. The following is a discussion of some of the unique features of each.

Step 15

Hayward Ecostar - Priced at $1269. Has a SVRS option for $1469. A 3 HP variable pump with a range of 600 to 3450 RPM. Can program 8 different speeds. One of the most efficient pumps based on 30 years of hydraulic design (volute, impeller). The controller and drive are mounted on the top of the motor. The controller can be removed and mounted on a wall up to 500' away. This drive can be integrated with Hayward's E-Command 4 automated control systems or most other manufacturers automated control systems. See EcoStar or EcoStar with SVRS for InyoPools links to these pumps.

Step 16

Hayward Ecostar Controller -

Step 17

Pentair Intelliflo - Three models are offered: two Variable Speed (VS) pumps; the 3050 for $930, the 3050 with SRVS for $1130; and one Variable Flow (VF)Pump for $1365. The VS pumps are programmed for up to 8 separate speeds and times. The VF pump is programmed to maintain up to 8 separate flow rates (GPM). Further, the VF pump can automatically calculate and program the minimum flow rate required for each task - filtering, heating, cleaning, spa jets, water features and more. All are 3 HP (3.95 THP) and operate in a range of 450-3450 RPM. The controller/drive is mounted on the top of the motor. There is no option with this pump to remove and mount the controller on a wall, but the drive can be wired to operate with Pentair's automated control systems including IntelliTouch, EasyTouch and SunTouch. It is not compatible with other manufacturers automated control systems. The Pentair Intelliflo pump uses its own Pentair designed motor and is not compatible with other motors for replacement. See IntelliFlo VS 3050 Pump or IntelliFlo VS Pump with SVRS or IntelliFlo VF Pump for InyoPools links to these pumps.

Step 18

Pentair Intelliflo Controller -

Step 19

Jandy VS FloPro - NEW - Priced at $TBD. A 2.0 THP variable speed pump with an operating range of 600-3450 RPM. The controller is plugged into the drive on top of the motor and can be mounted on a wall up to 20' away. The drive has two timers and 8 programmable speeds so two functions can be programmed to run automatically every day and 6 other functions can be manually initiated to run for a programmed amount of time. This pump is a smaller sized pump that the Jandy ePump discussed below. It is designed to handle less GPM for pools with limited water features. Pump Base Kit allows for easy retrofit replacement for the following manufacturer/models: Hayward Super Pumps; Pentair WhisperFlo and SuperFlo; Sta-Rite Dyna-Glas, DuraGlas, and Max-E-Pro; and Jandy PlusHP and MaxHP.

Step 20

Jandy VS FloPro Controller -

Step 21

Jandy ePump - Two pumps offered: JPR1.5 with a Total HP (THP) of 2.2 for $900, and JPR2.0 with a THP of 2.27 for $1091. Both operate in the range of 600-3450 RPM. The controller is the same on used on the Jandy FloPro discussed above. For this pump, however, the controller is a separate cost. If you choose not to purchase the controller, the ePump can be controlled by integrating it with the following automated pool control system. iAquaLink, Aqualink Touch, and Aqualink RS One Touch, and Aqualink PDA systems. See Jandy ePump VS 1.5 HP Pump or Jandy ePump VS 2.0 HP Pump for InyoPools' links to these pumps.

Step 22

Jandy ePump Controller - Not included with the pump. Priced separately at $388. See Jandy ePump Controller for InyoPools' link to this product.

Step 23

Speck Badu EcoMV - Two models offered: - EcoMV/72-V, $1320, 2.5 THP: and EconMV/72V1, #1381, 3.5 THP with SVRS. Both operate between 600 and 3450 RPM. The Controller mounted on top of the motor with the drive can be rotated 360 degrees for accessibility or can be mounted away from the pump. The pump can be programmed for 2 speeds / day Monday thru Friday and 3 speeds /day on Saturday and Sunday. Unique flow around basket design reduces blockages. See Speck Badu EcoMV Pump or Speck Badu EcoMV Pump with SVRS for InyoPools' links to these pumps.

Step 24

Speck Badu EcoMV Controller -

Step 25

Century VGreen Motors (9ECM27) - Priced at $699. - MOTOR ONLY with controller and drive. Century purchased AO Smith recently and is now the leading pump motor manufacturer. Many manufacturers used AO Smith induction motors in their pumps and this is also true of the newer variable speed motors. If you buy a new variable speed pump, you will likely be buying a Century motor. The Century V-Green motor is available with either a square or round interface to fit most pumps. It has 2.77 THP and can operate between 600 and 3450 RPM. The motor comes with the controller mounted on the top of the motor but this controller can be installed on a wall with the purchase of a separate kit. The drive is currently not compatible with any automated control system. See Century VGreen Motor with Sq. Flange or Century VGreen Motor with C Face (round for InyoPools' links to the two versions of this pump.

Step 26

Century VGreen Controller -

Step 27

Waterway Econo-Flo - Priced at $TBD. This pump uses the Century VGreen motor described above so it has all its features and operational characteristics.

Step 28

Waterway Econo-Flo Controller - Same as the Century VGreen Controller shown above.


(1 to 19 of 19)

Inyopools  Posted: 08/13/2016 12:16 PM  Inyo Product Specialist

jmcre8 - You usually set that by trial and error. You would bring the pump up at a higher speed to overcome the initial load of pushing the water up to the panels and get water flowing back down. Once the solar path is filled, the weight of the water coming down helps pull the water up and your pump has less work. At this point, you would step the pump's RPMs down to where the solar path stops flowing. Then step it back slightly to where the path flow again.

jmcre8  Posted: 08/13/2016 1:28 AM 

Looking for guidance when you have only SOLAR as a way of heating a pool. Wondering what the lowest RPM we can set with a Pentair variable motor when using Heliocol Solar Panels. We have a 1-story house, 8 panels 10.5' x 4' facing south-west.

Inyopools  Posted: 06/22/2016 12:21 PM  Inyo Product Specialist

Jandy Flo-pro 1.5 HP - Here's a link to the JEP-R Controller that has the programming instructions. You may already have this. To get clearer information on how to program your application, I would suggest calling Zodiac at 800-822-7933 and ask for Adam. He's expecting your call.

Anonymous  Posted: 06/18/2016 22:04 PM 

Hello, we have a new Jandy Flo-pro 1.5 HP with new Jandy sand filter. We live in Iowa, 22,000 gallon pool, 1 main drain and 1 skimmer. How do I know what setting to program the pump for? What speeds and what suggested times? The pump is very quiet, but I am very confused at to how to program. I am reading the manual, but struggling. Any suggestions? pool guy programmed but told us there was no timer, in reading the manual it clearly has times you can program

Shimon  Posted: 06/06/2016 19:33 PM 

Thank you. I am going to program it. I'm also looking for another pool service! Even at full speed, the VS is so much quieter than the old pump!

Inyopools  Posted: 06/06/2016 9:56 AM  Inyo Product Specialist

Shimon - Your proposed schedule sounds fine. The whole point of a VS pump is to be able to adjust the RPMs to only what's required as you schedule demonstrates. I don't understand the installer's comments on keeping the filtration schedule the same 8 hours as the old pump because you're in Miami. The only requirement on filtration is to turn the pool water over every 24 hours. If you double the run time and run the pump twice as long at 1/8th the energy, you are accomplishing that turnover. And his previous comment on the heater kicking in and out is not valid either. To run the heater, you will set the pump at whatever RPM is required to keep the heater running - usually 20-40 GPM. I'd have someone else program your VS pump.

Shimon  Posted: 06/04/2016 10:59 AM 


Thank you for this information. I've been trying to get answers to my questions and I have yet to find a clear answer. I live in Miami and have a pool that is appx 20,000 gallons. I have a salt water generator and a heat pump. Pool has a small waterfall, side vac for the cleaner, and two skimmers. Original pump was 1.5 HP single speed and was here when we bought the house. It just went out.

I had a Pentair 2VST installed by the company that provides our cleaning service. I was under the impression (based on everything I've read online and a discussion with someone in mechanical at the pool service company) that the new pump would be on a schedule, determined by which feature was being used (cleaner, SWG, heater, only circulation/skimmers). However, the installer told me he would keep the pump on the same 10am - 6pm schedule the old pump was on - using the mechanical timer - and the difference would just be the RPMs could be more dialed in on the VS pump. When I mentioned the schedule, he said those schedules do not apply to Miami due to the heat and humidity, as well as the sun exposure with our pool. I'll probably still be happier with the VS and there will be some savings I imagine as it should be more efficient, but I wish I could get a more definitive answer on this scheduling question. In summer, we do not need the heater. The cleaner only needs to run for two hours in the morning. I figure a summer schedule would be 10am-12pm enough rpms for cleaner (this would also run SWG) 12-4pm enough RPMs for SWG (should also pull through skimmers) and then 4pm - 10am enough RPMs for circulation or shut off at some point. Or 4pm - 8pm enough RPMs for waterfall and then 8pm to whatever for low circulation or shut off if more circulation is not necessary. This would be slightly modified for the heater during the cooler months.

A flow meter was not installed.

Does the installer just not want to take the time to program

Shimon  Posted: 06/03/2016 19:23 PM 

Thank you for having this informative page and answering questions. I'm a bit confused. I live in Miami, FL and our pool receives a lot of sun. It is approx 20,000 gallons and has a salt chlorine generator and heater. Also has a side vac as well as a small waterfall.

My 1.5 Pentair single speed just died. The noise alone was absurd. I'm having the Pentair 2VTS installed. My plan to was to create a schedule similar to what you have on this page. However, the installer told me that due to all factors involved (Miami temp, sun, features), the VS pump should be run for the same amount of time 10am - 6pm as the single speed. He said the speed will be determined by the needs of the cleaner. I did mention this type of schedule. He said there could be issues with the heater kicking off and on.

The installer works for the company we use to service our pool and they put in the SCG and heater. Is the installer correct? I can't tell if he just doesn't want to take the time to create a schedule like this or what he recommends is really what is best for our pool.

Thank you for taking the time to answer.

Mark  Posted: 05/29/2016 20:56 PM 

Looking into this VS motor. Current cost for power here is about .13/KWH. I currently use the Heyward single speed super pump, Model AO Smith C48K2N143B1 1HP motor and it's shows .75 KW. Now I assume that's the pump and motor assy, so the motor is SP1607Z1M. What Variable speed motor would be used for replacement? Could you tell me my cost savings based on the numbers I presented? I run my pump 24 Hrs a day once I open my pool. I also would not need speeds for heater or vacuum cleaner as I utilize a robot cleaner. Any information would be appreciated

Inyopools  Posted: 04/18/2016 12:05 PM  Inyo Product Specialist

Mark in Houston - I'm confused with your spa system specs: I would guess that your 400 gallon spa is missing a couple of zeros and 7 HP pumps are twice as large as the largest pumps we sell. And, generally, when people run their spas they run them at full speed, 3450 RPM, for full jet action. The variable speed savings comes from running the VSP at reduced speed for most of the time. If you are just going to circulate the spa water most of the time and only turn the jets on for a couple hours a day, you can see significant savings. Since I'm not sure of your requirements, I refer you to our complete list of "Variable Speed Pool Pumps". All of these VSPs are TEFC.

Mark in Houston  Posted: 04/15/2016 20:17 PM 

Do you have a controllable VSP pump with TEFC for a stand alone spa/hot tub? I have a large 400 gallon spa with two 7hp motors controlling 2 separate halves of spa. Just installed and my electric bills are quite shocking. Appreciate any advice to get my energy consumption lowered. Thank you.

Inyopools  Posted: 10/30/2015 13:40 PM  Inyo Product Specialist

KMS - Yes you can replace the 1/2 HP motor in your Pentair WhisperFlo pump with a VS V-Green 1.65 HP motor. It is a relatively easy replacement.

KMS  Posted: 10/28/2015 18:42 PM 

I have an existing single speed whisperflo 1/2 HP, 1.9 SF pump. Can I replace this (motor only) with Variable Speed V-Green 165 Pool Pump Replacement Motor (1.65 HP) listed on your website?

Inyopools  Posted: 07/23/2015 11:27 AM  Inyo Product Specialist

INDPNDT - With a VS pump, ou will have to do a little trial and error to optimize pump operation. See Steps #4 and #5 of this guide. If you are just circulating the water through the filter, I would start at 1200 RPM and run for 10 hours. If that doesn't keep your pool clean, run a little longer or faster. Some accompanying systems like a Salt Chlorine Generator need a minimum flow to operate. If the SCG "no flow" light goes on you may have to bump the RPMs up until that like goes off. If you have a suction cleaner, you will have to operate at about 2400 RPM for the period of time that the suction cleaner is operating.

INDPNDT  Posted: 07/21/2015 17:34 PM 

I just purchased a Pentair VS pump for my 22,000 gallon pool. I also have a Pentair Quad DE 100 sq.ft. filter that was installed at the same time. I'm trying to find out how long I should set the pump to run and at what speed for normal day to day filtering. If you know of a good source or calculator that would be much appreciated. Thank you for your help!!

Inyopools  Posted: 01/22/2015 10:24 AM  Inyo Product Specialist

Steve - It you are adding an additional pump and filter for your water feature, you don't need a VS pump. I would recommend a pump/  filter set like Hayward Super Pump 1 HP SINGLE Speed W/ C1200 120 Sq. Ft. Cartridge Filter. If you are adding this feature into your current pump system, I would recommend buying a mid size VS pump ~ 2-3 THP [HP x SF).

Steve  Posted: 01/19/2015 15:28 PM 

I'm looking at installing at total of 72 inches of water flumes (shear type from Brilliant Wonders. What pump and filter combination would you recommend, and is variable pump a good upgrade option?

Inyopools  Posted: 12/21/2014 9:30 AM  Inyo Product Specialist

Dick - I would have recommended a larger VS pump - 1.5 or 2 HP for you size pool. The 1.0 HP pump will probably work especially if it has a SF of 1.5, but you will have to run it at a higher RPM to filter that much water. This equates to higher operational costs.

Dick  Posted: 12/17/2014 14:35 PM 

Hi I just purchased a Jandy 1HP varible pump. With the controller. I paid $670 for it. My pool man installed it for $75. Do you think that this is a good enough pump for a 25000 gallon pool?